There are many options for organizing floors in a private house, among which the floor on the ground does not take the last place. This technology is one of the inexpensive and this method of organizing floors is used in houses where there is no basement or basement.
Many people believe that the floor on the ground is simple and easy to construct. You don't even have to walk around the bush, the Internet is full of stories and photographs, when the black earth extracted when digging a trench under the foundation is thrown into the house. Subsequently, sand is poured onto it, rammed, waterproofing is spread and a screed is made on top of this base! This is fundamentally contrary to technology!
Floor on the ground is a complex multi-layer structure that requires the owner's knowledge and attention to the builders when organizing such work. Incorrect foundation preparation is fraught with big problems. My friends, with all their knowledge of the topic of construction, were convinced by their own example that even correct the preparation of the foundation is not perfect.
Correct preparation of the base means such a preparation in which long-term use of the floor will never result in its subsidence.
So ...
After the basement of the house was ready and mothballed for the winter, it was decided to organize the base for the floors before the cold weather. The fertile soil layer was removed to a thickness of 35-40 cm (by 1.5 shovel bayonets) inside the house, and thus the level of black soil on the site was slightly raised ...
Further, this pit is filled with sand and gravel mixture, followed by compaction. Then sand was poured in layers, each layer no more than 15 cm with double ramming... There were 5 such layers and in this form the base stood all winter. Moreover, while the house was being built (3 years), the foundation was unchanged all this time.
Further, everything is standard ...
Waterproofing, insulation, another waterproofing film, mesh, fittings, underfloor heating and screed.
It would seem that 3 years have passed, of course, the floor on the ground will not go anywhere and will not sag, but n-n-n-e-t.
A month ago, it was noticed that the floor became lower.
How was it noticed?
There is a gap between the laminate and the skirting board, as the laminate is on the screed and the skirting is attached to the walls. The floors on the ground assume just such a device that the screed is in no way connected with the walls of the building. The floor on the ground is an independent structure.
Floor shrinkage by 3 mm in one room:
Floor shrinkage by the same amount in another room:
And there are times when the plinth hangs in the air, coming off the laminate by 1 or even 2 centimeters! Similar problems accompany those who, instead of sand and gravel, pour black soil into the base of the floor, or simply the layers are poorly compacted. Millimeters are not terrible, but when there is a shrinkage of several centimeters, it breaks all communications passing through the floors.
In the case of this house, to say that the foundation was prepared incorrectly? No, everything was done according to technology! No one drove the horses, the soil at the base of the floor was compacted, and then stood in the open air for 2 years, then another year under the roof, and only after 3 years the screed was poured. The engineers agree here that the foundation was not compacted enough.
Therefore, in order not to end up at a broken trough, it is so important to follow the craftsmen and follow the soil compaction technology. In general, any soil for several more years will be compacted by itself, even after it is compacted by mechanized methods.